Use the Google Analytics Event Tracking Code Generator to create the onclick goal. Note that if you are logged in and the analytics code is hidden then clicking the link will produce an error. To test the goal make sure you are logged out.
Note that we are only adding one category name when we setup the goal but we fill out several more variables in the onclick code. We do this because the onclick code requires a category, an action and a value.
Goals do NOT register immediately so after you set one up you will have to click on the phone number, then check a few days later to make sure it was recorded.
Be sure to note if the site is using an old classic analytics code you should upgrade to universal analytics.